1. Special motion types Special interpolation types Helical motion
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program
Spiral motion
Cylindrical interpolation
Why it is required
Programming considerations
Polar coordinate interpolation
Live tooling and C axis
Programming
Coordinate system

2. Relates to machining and turning centers
Special
Interpolation
Types
Relates to machining and turning centers

3. G01 – straight line motion G02 & G03 – circular motion
Special interpolation types
You know the three basic types of motion:
These motion types are used in almost all CNC machining center and turning center programs.
G00 – rapid motion
G01 – straight line motion
G02 & G03 – circular motion
All control manufacturers have developed other motion types to handle special motion problems…
Thread milling: helical interpolation
Taper thread milling: spiral interpolation
3d machining on mill: nurbs interpolation
Rotary axis on mill: cylindrical interpolation
Rotary axis on lathe: polar coordinate interpolation

4. Relates only to machining centers
Helical
interpolation
Relates only to machining centers

5. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

6. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

7. Threads per inch Inch: ¾ - 10 Diameter Pitch Metric: 25 – 1.5 Diameter
Helical interpolation
Thread designation:
Threads per inch
Inch:
Metric:
Diameter
¾ - 10
25 – 1.5
Pitch = 1/ threads per inch
Pitch
Diameter

8. Blind hole Through hole Helical interpolation
Blind versus through holes:
If machined in vertical orientation, chips collect at hole bottom. Machine thread from bottom to top to minimize chip problems
Blind hole
Through hole

9. Blind hole Through hole Helical interpolation
Blind versus through holes:
If machined in vertical orientation, chips fall through hole. Machining direction is not so important.
Blind hole
Through hole

10. Climb milling Helical interpolation Climb versus conventional milling:
(Right hand cutter)
Cutter will move in a counter-clockwise direction from bottom to top of hole

11. Cutter will move in a clockwise direction from top to bottom of hole
Helical interpolation
Climb versus conventional milling:
If machine has sufficient rigidity, climb milling leaves a better finish
Conventional milling
(Right hand cutter)
Cutter will move in a clockwise direction from top to bottom of hole

12. G42 – Conventional milling
Helical interpolation
Cutter radius compensation
As with any contour milling operation…
…you can use cutter radius compensation when thread milling to let the operator control hole size
G41 – Climb milling
G42 – Conventional milling

13. This is the motion type required for thread milling
Helical interpolation
Helical interpolation
This is the motion type required for thread milling
Two axes (usually X & Y) move in a circular fashion
On axis (usually Z) moves in a linear fashion

14. Helical interpolation
XY move in circular fashion
Z moves in linear fashion

15. Helical interpolation
XY move in circular fashion
Z moves in linear fashion

16. Helical interpolation
XY move in circular fashion
Z moves in linear fashion

17. Helical interpolation
XY move in circular fashion
Z moves in linear fashion

18. G02 – Clockwise G03 – Counter clockwise
Helical interpolation
Helical interpolation
As with circular motion…
G02 – Clockwise
G03 – Counter clockwise
The Z departure will be related to the thread pitch and how much of a full circle is being commanded (more on this in a moment)
The only difference from circular motion is that helical motion requires a Z departure

19. Helical interpolation
Arc-in approach and escape
Move to center of approach radius

20. Helical interpolation
Arc-in approach and escape
Instate cutter radius compensation

21. Helical interpolation
Arc-in approach and escape
Approach radius
Arc-in approach

22. Helical interpolation
Arc-in approach and escape
Machine thread

23. Helical interpolation
Arc-in approach and escape
Machine thread

24. Helical interpolation
Arc-in approach and escape
Machine thread

25. Helical interpolation
Arc-in approach and escape
Machine thread

26. Helical interpolation
Arc-in approach and escape
Machine thread

27. Arc-in approach and escape are required to eliminate witness marks.
Helical interpolation
Arc-in approach and escape
Escape radius
Arc-in approach and escape are required to eliminate witness marks.
Arc-off escape

28. Even approach and escape movements must be helical motions
Helical interpolation
Z departure
You must synchronize the Z departure based upon…
Percentage of a full circle being machined
Pitch of thread
Even approach and escape movements must be helical motions

29. Helical interpolation
Z departure
Move to center of approach radius

30. Helical interpolation
Z departure
Instate cutter radius compensation

31. ¼ of full circle: depart in Z ¼ of pitch
Helical interpolation
Z departure
Approach radius
(1/4 of full circle)
¼ of full circle: depart in Z ¼ of pitch
Arc-in approach

32. Helical interpolation
Z departure
Machine thread

33. ¼ of full circle: depart in Z ¼ of pitch
Helical interpolation
Z departure
¼ of full circle: depart in Z ¼ of pitch
Machine thread

34. ¼ of full circle: depart in Z ¼ of pitch
Helical interpolation
Z departure
¼ of full circle: depart in Z ¼ of pitch
Machine thread

35. ¼ of full circle: depart in Z ¼ of pitch
Helical interpolation
Z departure
¼ of full circle: depart in Z ¼ of pitch
Machine thread

36. ¼ of full circle: depart in Z ¼ of pitch
Helical interpolation
Z departure
¼ of full circle: depart in Z ¼ of pitch
Machine thread

37. ¼ of full circle: depart in Z ¼ of pitch
Helical interpolation
Z departure
Escape radius
¼ of full circle: depart in Z ¼ of pitch
Arc-off escape

38. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

39. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

40. Helical interpolation
Thread milling cutter types
Like a slot milling cutter with thread form on outside diameter
Pros: Inexpensive, can machine any pitch
Cons: Requires one full circle per pitch

41. Helical interpolation
Thread milling cutter types
Integral shank thread milling cutter made from hss, cobalt, or carbide
Pros: Can machine entire pitch in one circle
Cons: Expensive, can only machine one pitch

42. This is becoming the most popular form of thread milling cutter
Helical interpolation
Thread milling cutter types
This is becoming the most popular form of thread milling cutter
Carbide inserted type
Pros: Can machine entire pitch in one circle, can machine any pitch (with different inserts), relatively inexpensive

43. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

44. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

45. Helical interpolation
Approach to thread milling
Climb or conventional milling?
The only reason to conventional mill…
…machine doesn’t have rigidity required to climb mill

46. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

47. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

48. Helical interpolation
Programming considerations
The trick to programming helical motion
Program normal circular motion in XY…
…and match the Z departure to the percentage of a full circle being machined

49. If the tool moves half a circle, it must depart ½ the pitch in Z
Helical interpolation
Programming considerations
Pitch
For every full circle motion in XY, the tool must move one full pitch in Z
If the tool moves half a circle, it must depart ½ the pitch in Z

50. Pitch Helical interpolation ¼ revolution in XY Depart ¼ pitch in Z
Programming considerations
¼ revolution in XY
Pitch
Depart ¼ pitch in Z
If pitch is (8 threads per inch)
Depart in Z
For every full revolution in XY, the tool must move one full pitch in Z
If the tool moves half a circle, it must depart ½ the pitch in Z

51. Pitch Helical interpolation ½ revolution in XY Depart ½ pitch in Z
Programming considerations
½ revolution in XY
Pitch
Depart ½ pitch in Z
If pitch is (8 threads per inch)
Depart in Z
For every full revolution in XY, the tool must move one full pitch in Z
If the tool moves half a circle, it must depart ½ the pitch in Z

52. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

53. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw is constant
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

54. Climb milling (feeding bottom to top in ccw direction)
Example program
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...
Climb milling (feeding bottom to top in ccw direction)
0.125 pitch

55. Helical interpolation
Program number
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

56. Helical interpolation
Thread mill size
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

57. Helical interpolation
Place thread mill in spindle
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

58. Helical interpolation
Start spindle
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

59. Helical interpolation
Rapid to center of approach radius
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

60. Helical interpolation
Approach in Z
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

61. Helical interpolation
Rapid through hole
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...
Starting Z position for helical move

62. Helical interpolation
Instate cutter comp.
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

63. Helical interpolation
Approach to hole
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...
Departing ¼ circle in XY
So depart in Z ¼ pitch (0.0312)
-0.7 minus is –0.6688

64. Helical interpolation
Mill half way around hole
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...
Departing ½ circle in XY
So depart in Z ½ pitch (0.0625)
minus is –0.6063

65. Helical interpolation
Mill other half
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...
Departing ½ circle in XY
So depart in Z ½ pitch (0.0625)
minus is –0.5438

66. Helical interpolation
Arc-off the hole
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...
Departing ¼ circle in XY
So depart in Z ¼ pitch (0.0312)
minus is –0.5126

67. Helical interpolation
Cancel cutter comp
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

68. Helical interpolation
Retract from hole
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

69. Helical interpolation
Return to zero return position
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

70. Helical interpolation
Optional stop
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

71. Helical interpolation
Program continues
Helical interpolation
O0001
(1" thread mill)
N150 T07 M06
N155 G90 G54 S600 M03 T08
N160 G00 X1.5 Y1.75
N165 G43 H07 Z0.1
N170 G00 Z-0.7 M08
N180 G01 G41 D37 X2.25 F40.0
N185 G03 X1.5 Y2.5 Z
R0.75 F6.0
N190 Y0.5 Z R1.0
N195 Y2.5 Z R1.0
N200 X0.75 Z R0.75
N205 G00 G40 X1.5
N210 G00 Z0.1 M09
N215 G91 G28 Z0 M19
N220 M01
N225...

72. Three axis motion is created Two axes (X and Y) are circular
Helical interpolation
Used to mill threads on machining centers
Three axis motion is created
Two axes (X and Y) are circular
One axis (Z) is linear
Final notes:
Male (outside diameter) threads are also possible
Motion resembles a cork-screw, but the radius of the cork-screw is constant
If the thread is so deep that one pass does not complete the thread, you can make multiple passes (just keep departing in Z in even increments of the pitch)
Topics:
Thread milling terminology
Thread milling cutter types
Approach to thread milling
Programming considerations
Example program

73. Relates only to machining centers
Spiral
interpolation
Relates only to machining centers

74. Three axis motion is created Two axes (X and Y) are spiral
Spiral interpolation
Used to mill taper threads on machining centers
Three axis motion is created
Two axes (X and Y) are spiral
One axis (Z) is linear
Motion resembles a cork-screw, and the radius of the cork-screw constantly changes
Topics:
Why spiral interpolation is required

75. Three axis motion is created Two axes (X and Y) are spiral
Spiral interpolation
Used to mill taper threads on machining centers
Three axis motion is created
Two axes (X and Y) are spiral
One axis (Z) is linear
Motion resembles a cork-screw, and the radius of the cork-screw constantly changes
Topics:
Why spiral interpolation is required

76. Taper thread milling cutter
Spiral interpolation
Taper thread milling cutter
Consider what would happen with helical motion if milling top to bottom
Thread to mill

77. If you must make a perfect taper thread, you can’t use helical motion!
Spiral interpolation
If you must make a perfect taper thread, you can’t use helical motion!
Nasty witness mark
Taper thread milling cutter
Unfortunately, not all control manufacturers offer spiral interpolation
Actual size: Tangent of taper angle times pitch
Consider what would happen with helical motion if milling top to bottom
Note that you can simulate spiral motions with parametric programming
If taper is degrees and pitch is 0.125, gap will be inch
Thread to mill
Though exaggerated, this shows what the workpiece would look like after machining

78. Three axis motion is created Two axes (X and Y) are spiral
Spiral interpolation
Used to mill taper threads on machining centers
Three axis motion is created
Two axes (X and Y) are spiral
One axis (Z) is linear
Motion resembles a cork-screw, but the radius of the cork-screw constantly changes
Topics:
Why spiral interpolation is required

79. Relates to machining and turning centers
Cylindrical
interpolation
Relates to machining and turning centers

80. G02/G03 now possible with rotary axis
Cylindrical interpolation
Used to mill contours around a cylinder
Used with rotary axis
G02/G03 now possible with rotary axis
You can treat rotary axis as linear
Allows feedrate to be specified in IPM
Just about any contour can be milled around the outside of a cylindrical object
Topics:
Why cylindrical interpolation is required
Programming considerations

81. G02/G03 now possible with rotary axis
Cylindrical interpolation
Used to mill contours around a cylinder
Used with rotary axis
G02/G03 now possible with rotary axis
You can treat rotary axis as linear
Allows feedrate to be specified in IPM
Just about any contour can be milled around the outside of a cylindrical object
Topics:
Why cylindrical interpolation is required
Programming considerations

82. Many machining centers are equipped with rotary axes
Cylindrical interpolation X Y Z
Many machining centers are equipped with rotary axes A

83. Cylindrical interpolationX Y Z A
Cylindrical interpolation allows you to program the rotary axis as if it is a linear axis!
Without cylindrical interpolation, you’re quite limited to what can be done with and end mill
No circular motion (G02/G03) is possible
Feedrate must be specified in degrees per minute
Calculating positions can be difficult

84. G02/G03 now possible with rotary axis
Cylindrical interpolation
Used to mill contours around a cylinder
Used with rotary axis
G02/G03 now possible with rotary axis
You can treat rotary axis as linear
Allows feedrate to be specified in IPM
Just about any contour can be milled around the outside of a cylindrical object
Topics:
Why cylindrical interpolation is required
Programming considerations

85. G02/G03 now possible with rotary axis
Cylindrical interpolation
Used to mill contours around a cylinder
Used with rotary axis
G02/G03 now possible with rotary axis
You can treat rotary axis as linear
Allows feedrate to be specified in IPM
Just about any contour can be milled around the outside of a cylindrical object
Topics:
Why cylindrical interpolation is required
Programming considerations

86. Cylindrical interpolationX Y Z A

87. Cylindrical interpolation
With Fanuc, a G07.1 is used to instate
An A word specifies this distance
G07.1 A2.75 X Y Z A
The control must be told the distance from the workpiece center to the work surface

88. Cylindrical interpolation
Coordinate system for cylindrical interpolation 5 6
0.5 R 1 2 3 4 7 8
0.375 R
X axis
1.0 in
2.0 in
3.0 in
A axis
deg
180
360 90
270

89. Note that these are true arcs
Cylindrical interpolation
A axis
deg
180
360 90
270 5 6
0.5 R 1 2 3 4 7 8
0.375 R
X axis
1.0 in
2.0 in
3.0 in 1 2 4
Note that these are true arcs 3 5 6

90. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 1 2 4 3 5 6

91. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 2 4 3 5 8 6 7

92. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 2 4 3 5 8 6 7

93. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 4 3 5 8 6 7

94. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 4 3 5 8 6 7

95. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 4 3 5 8 6 7

96. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 5 8 6 7

97. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 5 8 6 7

98. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 6 7

99. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 6 7

100. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 7

101. Cylindrical interpolation
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 7

102. Cylindrical interpolation
N005 G54 G90 S500 M03
N010 G00 X3.0 Y0 A0
N015 G43 H01 Z3.1
N020 G01 Z2.75 F4.0
N025 G07.1 A2.75
N030 G01 A55.0 F10.0
N035 G02 X2.5 A90.0 R0.5
N040 G01 X1.5
N045 G03 X1.125 A120.0 R0.375
N050 G01 A165.0
N055 X3.0 A270.0
N060 Z360.0
N065 Z3.1
N070 G07.1 A0
N075 G91 G28 X0 Y0 Z0
N080 M30
Cylindrical interpolation
0.5 R
X axis
1.0 in
2.0 in
3.0 in 2 7 8 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 8

103. Cylindrical interpolation
N005 G54 G90 S500 M03
N010 G00 X3.0 Y0 A0
N015 G43 H01 Z3.1
N020 G01 Z2.75 F4.0
N025 G07.1 A2.75
N030 G01 A55.0 F10.0
N035 G02 X2.5 A90.0 R0.5
N040 G01 X1.5
N045 G03 X1.125 A120.0 R0.375
N050 G01 A165.0
N055 X3.0 A270.0
N060 Z360.0
N065 Z3.1
N070 G07.1 A0
N075 G91 G28 X0 Y0 Z0
N080 M30
Cylindrical interpolation
0.5 R
X axis
1.0 in
2.0 in
3.0 in 2 7 8
Instate cylindrical interpolation, specify distance from center to work surface 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 8

104. Note that feedrate can now be specified in per minute fashion
N005 G54 G90 S500 M03
N010 G00 X3.0 Y0 A0
N015 G43 H01 Z3.1
N020 G01 Z2.75 F4.0
N025 G07.1 A2.75
N030 G01 A55.0 F10.0
N035 G02 X2.5 A90.0 R0.5
N040 G01 X1.5
N045 G03 X1.125 A120.0 R0.375
N050 G01 A165.0
N055 X3.0 A270.0
N060 Z360.0
N065 Z3.1
N070 G07.1 A0
N075 G91 G28 X0 Y0 Z0
N080 M30
Cylindrical interpolation
0.5 R
X axis
1.0 in
2.0 in
3.0 in 2 7 8
Note that feedrate can now be specified in per minute fashion 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 8

105. Circular motions are now permissible
N005 G54 G90 S500 M03
N010 G00 X3.0 Y0 A0
N015 G43 H01 Z3.1
N020 G01 Z2.75 F4.0
N025 G07.1 A2.75
N030 G01 A55.0 F10.0
N035 G02 X2.5 A90.0 R0.5
N040 G01 X1.5
N045 G03 X1.125 A120.0 R0.375
N050 G01 A165.0
N055 X3.0 A270.0
N060 Z360.0
N065 Z3.1
N070 G07.1 A0
N075 G91 G28 X0 Y0 Z0
N080 M30
Cylindrical interpolation
0.5 R
X axis
1.0 in
2.0 in
3.0 in 2 7 8
Circular motions are now permissible 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 8

106. Cancel cylindrical interpolation
N005 G54 G90 S500 M03
N010 G00 X3.0 Y0 A0
N015 G43 H01 Z3.1
N020 G01 Z2.75 F4.0
N025 G07.1 A2.75
N030 G01 A55.0 F10.0
N035 G02 X2.5 A90.0 R0.5
N040 G01 X1.5
N045 G03 X1.125 A120.0 R0.375
N050 G01 A165.0
N055 X3.0 A270.0
N060 Z360.0
N065 Z3.1
N070 G07.1 A0
N075 G91 G28 X0 Y0 Z0
N080 M30
Cylindrical interpolation
0.5 R
X axis
1.0 in
2.0 in
3.0 in 2 7 8
Cancel cylindrical interpolation 1 3
0.375 R 4 5 6
A axis
deg
180
360 90
270 8

107. G02/G03 now possible with rotary axis
Cylindrical interpolation
Used to mill contours around a cylinder
Used with rotary axis
G02/G03 now possible with rotary axis
You can treat rotary axis as linear
Allows feedrate to be specified in IPM
Just about any contour can be milled around the outside of a cylindrical object
Topics:
Why cylindrical interpolation is required
Programming considerations

108. Relates only to turning centers
Polar coordinate
interpolation
Relates only to turning centers

109. These turning centers do secondary operations!
Polar coordinate interpolation
Used to mill contours on a turning center
Many turning centers have three axes
X, Y, and C
The C axis is a rotary axis
Within the spindle
The main spindle has two modes
Turning mode and C axis mode
Tools in the turret can rotate (live tooling)
These turning centers do secondary operations!
Topics:
Live tooling and C axis
Programming
Coordinate system
Example program

110. These turning centers do secondary operations!
Polar coordinate interpolation
Used to mill contours on a turning center
Many turning centers have three axes
X, Y, and C
The C axis is a rotary axis
Within the spindle
The main spindle has two modes
Turning mode and C axis mode
Tools in the turret can rotate (live tooling)
These turning centers do secondary operations!
Topics:
Live tooling and C axis
Programming
Coordinate system
Example program

111. Turret
Rotating tool in turret
Chuck
Could be: Drill
Tap
Reamer
End mill
Etc.

112. Again, this kind of turning center can perform machining center-like operations!
Turret
Rotating tool in turret
Chuck
Could be: Drill
Tap
Reamer
End mill
Etc.
Parallel
To X
C axis
Spindle incorporates rotary axis

113. These turning centers do secondary operations!
Polar coordinate interpolation
Used to mill contours on a turning center
Many turning centers have three axes
X, Y, and C
The C axis is a rotary axis
Within the spindle
The main spindle has two modes
Turning mode and C axis mode
Tools in the turret can rotate (live tooling)
These turning centers do secondary operations!
Topics:
Live tooling and C axis
Programming
Coordinate system
Example program

114. These turning centers do secondary operations!
Polar coordinate interpolation
Used to mill contours on a turning center
Many turning centers have three axes
X, Y, and C
The C axis is a rotary axis
Within the spindle
The main spindle has two modes
Turning mode and C axis mode
Tools in the turret can rotate (live tooling)
These turning centers do secondary operations!
Topics:
Live tooling and C axis
Programming
Coordinate system
Example program

115. Programming the C axis M codes select spindle mode
M81: Normal turning mode
M82: C axis mode
Machine used as a normal two-axis turning center
M code numbers vary from builder to builder

116. M code numbers vary from builder to builder
Programming the C axis
M codes select spindle mode
M81: Normal turning mode
M82: C axis mode
C axis rotary device engaged:
Full rotary axis
Can be used as an indexer
Spindle speed (S word) now activates turret tool
Feedrate must be in G98 mode
M code numbers vary from builder to builder

117. Your lesson text includes examples of C axis programming
Programming the C axis
M codes select spindle mode
M81: Normal turning mode
M82: C axis mode
Your lesson text includes examples of C axis programming
Similarities to linear axis:
G00 & G01
Incremental and absolute
Program zero assignment

118. These turning centers do secondary operations!
Polar coordinate interpolation
Used to mill contours on a turning center
Many turning centers have three axes
X, Y, and C
The C axis is a rotary axis
Within the spindle
The main spindle has two modes
Turning mode and C axis mode
Tools in the turret can rotate (live tooling)
These turning centers do secondary operations!
Topics:
Live tooling and C axis
Programming
Coordinate system
Example program

119. These turning centers do secondary operations!
Polar coordinate interpolation
Used to mill contours on a turning center
Many turning centers have three axes
X, Y, and C
The C axis is a rotary axis
Within the spindle
The main spindle has two modes
Turning mode and C axis mode
Tools in the turret can rotate (live tooling)
These turning centers do secondary operations!
Topics:
Live tooling and C axis
Programming
Coordinate system
Example program

120. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis C+ X+
Note that the machine cannot move in this direction! C- X-
Viewing chuck from tailstock side

121. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+ C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

122. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+ C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

123. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+
X+ and C+ motion C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

124. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+
X+ and C- motion C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

125. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+
X+ and C+ motion C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

126. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+
X+ and C- motion C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

127. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+
X+ and C+ motion C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

128. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+
X+ and C- motion C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

129. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+
X+ and C+ motion C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

130. Axis layout for rotary axis
Coordinate system
Axis layout for rotary axis
Milling cutter C+ X+
X+ and C- motion C-
Yet by combining X and C motion, this shape can be milled! X-
Viewing chuck from tailstock side

131. Coordinate system
Polar coordinate interpolation lets you handle the C axis as if it is a linear axis! X+
X3.2 C0
Remember, X is in diameter C+ C-
Program zero X-
Viewing chuck from tailstock side

132. Coordinate system
Polar coordinate interpolation lets you handle the C axis as if it is a linear axis! X+
X2.5 C0 C+ C-
Program zero X-
Viewing chuck from tailstock side

133. Coordinate system
Polar coordinate interpolation lets you handle the C axis as if it is a linear axis! X+
X2.5 C C+ C-
Program zero
Of course the tool can’t actually move in this fashion X-
Viewing chuck from tailstock side

134. Coordinate system
Polar coordinate interpolation lets you handle the C axis as if it is a linear axis! X+
X0 C C+ C-
Program zero X-
Viewing chuck from tailstock side

135. Coordinate system
Polar coordinate interpolation lets you handle the C axis as if it is a linear axis! X+
X-2.5 C C+ C-
Program zero X-
Viewing chuck from tailstock side

136. Coordinate system
Polar coordinate interpolation lets you handle the C axis as if it is a linear axis! X+
X-2.5 C0.5176 C+ C-
Program zero X-
Viewing chuck from tailstock side

137. Coordinate system
Polar coordinate interpolation lets you handle the C axis as if it is a linear axis! X+
X0 C1.4785 C+ C-
Program zero X-
Viewing chuck from tailstock side

138. Coordinate system
Polar coordinate interpolation lets you handle the C axis as if it is a linear axis! X+
X2.5 C0.5176 C+ C-
Program zero X-
Viewing chuck from tailstock side

139. Even circular motion is allowed in this fashion! X2.5 C0
Coordinate system
Polar coordinate interpolation makes programming contouring motions easy!
Polar coordinate interpolation lets you handle the C axis as if it is a linear axis! X+
Even circular motion is allowed in this fashion!
X2.5 C0
See lesson text for a full example program C+ C-
Program zero X-
Viewing chuck from tailstock side

140. These turning centers do secondary operations!
Polar coordinate interpolation
Used to mill contours on a turning center
Many turning centers have three axes
X, Y, and C
The C axis is a rotary axis
Within the spindle
The main spindle has two modes
Turning mode and C axis mode
Tools in the turret can rotate (live tooling)
These turning centers do secondary operations!
Topics:
Live tooling and C axis
Programming
Coordinate system
Example program

141. Many turning centers have three axes The C axis is a rotary axis
Polar coordinate interpolation
Used to mill contours on a turning center
Many turning centers have three axes
X, Y, and C
The C axis is a rotary axis
Within the spindle
The main spindle has two modes
Turning mode and C axis mode
Tools in the turret can rotate (live tooling)
Again, full example program is shown in your lesson text
These turning centers do secondary operations!
Topics:
Live tooling and C axis
Programming
Coordinate system
Example program